Jib-crane.



JIB CRANE. APPLICATION FILED' MAY 6.1910.

Patented Jan. s, 1911.

` SHEETS-SHEET 1.

P. sodium.

nB GRANE.

APPLIOATIN FILED MAY 6,1910. y y 980,846, v Patented Jan. 3, 1911.

Unire ir'rs :TIB-CRANE.

Specication of Letters Patent.

rat-entes aan. s, ieri.

Application filed May 6, 1910. Serial No. 559,727'.

invention, such as will enable others skilled in the artto which it appertains to make anduse the same My invention relates to jib cranes and has for its object to provide a jib crane in which not only the jib, but also the post may be readily turned down into the horizontal psitionand turned up again so that the ieight of the entire crane when not in use is reduced to a minimum which is of vgreat importance in many cases.

In the accompanying drawings: Figure l isa side elevation and Fig. 2 a plan of a 'ib crane const-ructed in accordance with my invention, Fig. 3 is a side elevation and Fig. 4 -a plan of a. modification and Fig. 5 is 4'a diagrammatical side elevation of a further modification of my improved jib crane.

My improved jib crane consists of a horizontal base beam a on which is pivoted the jib bat c,and the post ci at c2. rifhe jib b carries at its outer end as usual a pulley 1" for the load rope and besides a pulleyor set of ulleys 112 and one or more guide pulleys -4 or the jib actuating rope s2. The load .ope s runs from the pulley r to the load windlass h for raising and lowering' the load. The jib actuating rope s2 which' has one end secured to the jib b at z', irst'pr s around one of the pulle s r3 on the post '7., then over the guide pu' pulley r2 of the jib 7ot and then over another pulley r of the jib lfand the pulleys 7' at the outer end of the post d to the j ib windlass h2. Besides a guide pulley 7' is journaledin the post a?. `The outer end of the post d is connectedto the base beam by members adapted to limit the upward movement of the post. According to Figs. Aland 2 these members consist each of two ro'ds e pivotally connected and having their outer ends pivoted to the outer end of the post and to the base beam a respectively, the two parts c e 'of the tie-rod being pivoted at f ley r4 and around while the dotted lines indicate the position of the parts when the jib and the post are I"olded down. In order to bring the folded down crane into position tit for use first the jib actuating windlass 71,2 is turned whereby the puileys r3 at the outer end of the post d are drawn toward the pulle s r2 at the outer end of the jib b. rIhe weightof the long j ib b being greaterthan the weight of the post d, the former remains in its horizontal vposition indicated in dotted lines in Fig.' l until the post d has come into the position shown in full lines in Fig. 1 and thetie-rodse e have been stretched, whereby the u ward movement of the post is arrested. I then the windlass k2 continues to turn the pulley r2 and the jib will move toward thepbst. d the latter being stationary so that` the jib will be raised and ,when'lt has reached its desired position the windlass ft2-is sto pcd and the load maybe raised or lowered by the windlass It as usual. v i

When itis desired to fold down the crane the windlassjt2 is turned in thel opposite direction whereby first thejib b will be lowered into the horizontal position indicated in 'dotted lines in Fig. l, this jib being heavier than the post, while the post'd is held in its raised position by the action of the ropes on the pulleys?a3 andby the tierods e e. Vhen, however, the .windlass continuesto move the post d will turn down owing to gravity into the horizontal position indicated in dottedlines in Fig. 1, the tierods e e turning relativei to each other. In order that in the folde down position of the crane the rope s may not come into contact with the rope s2 and become entangled therewith the guide pulleys r* and 15 are so mounted in the jib b and inthe post d respectively that the lengths of the rope sextending tween the jib and the post come on the to p side of the said ulleys 'l and thus are raise above the to the folded down jib and post w creas-the rope s runs in a diiierent plane to the bottom edge of the jib.

e ges of The horizontal base beam a is adapted to l revolve on a central pivotn or to run on cirrods e2 are substituted, the lower ends of 11? which are provided with studs e3 adapted to slide in a transverse guide g tast on the buse beam. I

`,y ln the modification shown in Fig. 5 for the tie-rods e e a chain or Wire rope e3 is substituted, the lower end `ot which is iastened at c* to the base beam.

ln the modiicationshown in Figs. 3 end the .upward movement oi' the post is limited by the rods e2 when the studs reach. the'leit hand end of the guide g. In the modification shown in ig. 5 the upward movement of the .post is stopped 'when the chain or rope e3 is stretched.

in any cese the jib and the post have to be so constructed and arrzmged that the one does not interfere with the moven'ieuts of the other. Such a construction and arrangement is clearly shown in the drawings.

Claims:

l. In a jlb crane, the combination oit a base beam and a jib and a post having their bottom ends pivoted to such base beam, the

` jib being heavier than the pest, pulleys mounted in the outer ends of the jib and ei the post, a jib actuat'in rope runningl around such pulleys, means for actuating such rope whereby the jib and the beam may he raised and lowered, and. means for connecting the post and the brise beam and adapted to limit the upward movement of the post, substantially es and for the purpose described.

i2, in a jib crane the combination of a base beam and a jib and a post having their botn tom ends pivoted to such base beam the jib eeoelie i being heavier than the post, pulleys mounted in the outer ends of the jiband the post, a jib actuating rope running around such pulleys, means for actuating such rope whereby the jib and the beam may be raised and lowered, means for connecting the post and the base beam and adapted to limit the upward movement of the ost, a load pulley mounted ou the jib, a oad rope running;- on the said load pulley, guide pulleys for the jib :uztuating` rope mounted in the jib and in the post and adapted to keep the said jib ac-y tuating rope at all times clear ot the Said load rope, substantially7 as and for the purpose described.

3. .in a 3io clane the combination of a base beam and a, jib and a post having their bottom ends pivoted to such base beam, the jib being heavier than the post, pulleys mounted in the outer ends of the jib and the post, a jib actuating;l yrope runningr around such pulleys, means for actuating such rope, whereby the jib and the beam may be raised and lowered, and tie-rods havingtheir outer ends pivotcd to the post and the hase beam respectively and adapted to limit the upward movement of the post, substantially as and :tor the purpose described.

In testimony whereof, l aiiix my signa ture, in presence ot two Witnesses.

FiyllillitiCH4 SGCHOR.

Witnesses ARTHUR BAUMANN, AUGUST Focene. 

